Synthesis and Oxidation of Dirhenium C4, C6, and C8 Complexes of the Formula (5-C5
详细信息 查看全文
- 作者：Wayne E. Meyer ; Angelo J. Amoroso ; Clemens R. Horn ; Monika Jaeger ; and J. A. Gladysz
- 刊名：Organometallics
- 出版年：2001
- 出版时间：March 19, 2001
- 年：2001
- 卷：20
- 期：6
- 页码：1115 - 1127
- 全文大小：310K
- 年卷期：v.20,no.6(March 19, 2001)
- ISSN：1520-6041
文摘
The racemic methyl complexes (
5-C5Me5)Re(NO)(PR3)(CH3) (R: b, 4-C6H4CH3; c, 4-C6H4-t-C4H9; d, 4-C6H4C6H5; e, c-C6H11), which feature phosphines that are more electron richand/or bulkier than P(C6H5)3, are elaborated by reactions with HBF4·OEt2/chlorobenzene,HC
CH or HCCCCSiMe3, and t-BuOK to give the alkynyl complexes (5-C5Me5)Re(NO)(PR3)(CCH) (3b,c) and (5-C5Me5)Re(NO)(PR3)(CCCCSiMe3) (7b-e). The latter areconverted (K2CO3/MeOH or wet n-Bu4N+F-) to butadiynyl complexes (8b-e). Homo- or cross-couplings (3b, 8b-e; Cu(OAc)2/pyridine) lead to the 
-butadiynediyl complex (5-C5Me5)Re(NO)(PR3)(CC)n(R3P)(ON)Re(5-C5Me5) (4b; n = 2) and analogous -hexatriynediyl (10b;n = 3) and -octatetraynediyl (9b-e; n = 4) species. Oxidation of 4b by AgSbF6 (ca. 1:1 or1:2) gives the radical cation 4b
+SbF6- or the dication 4b2+(SbF6-)2. These isolable compoundsexhibit delocalized mixed-valence and cumulenic electronic ground states, respectively. Thecyclic voltammograms of 9b-e and 10b show oxidations to analogous species, with muchbetter chemical reversibilities than for the P(C6H5)3 analogues. However, these longer chainsystems decompose rapidly at -78 
C and could not be isolated or spectroscopicallycharacterized.
5-C5Me5)Re(NO)(PR3)(CH3) (R: b, 4-C6H4CH3; c, 4-C6H4-t-C4H9; d, 4-C6H4C6H5; e, c-C6H11), which feature phosphines that are more electron richand/or bulkier than P(C6H5)3, are elaborated by reactions with HBF4·OEt2/chlorobenzene,HCCH or HCCCCSiMe3, and t-BuOK to give the alkynyl complexes (5-C5Me5)Re(NO)(PR3)(CCH) (3b,c) and (5-C5Me5)Re(NO)(PR3)(CCCCSiMe3) (7b-e). The latter areconverted (K2CO3/MeOH or wet n-Bu4N+F-) to butadiynyl complexes (8b-e). Homo- or cross-couplings (3b, 8b-e; Cu(OAc)2/pyridine) lead to the -butadiynediyl complex (5-C5Me5)Re(NO)(PR3)(CC)n(R3P)(ON)Re(5-C5Me5) (4b; n = 2) and analogous -hexatriynediyl (10b;n = 3) and -octatetraynediyl (9b-e; n = 4) species. Oxidation of 4b by AgSbF6 (ca. 1:1 or1:2) gives the radical cation 4b+SbF6- or the dication 4b2+(SbF6-)2. These isolable compoundsexhibit delocalized mixed-valence and cumulenic electronic ground states, respectively. Thecyclic voltammograms of 9b-e and 10b show oxidations to analogous species, with muchbetter chemical reversibilities than for the P(C6H5)3 analogues. However, these longer chainsystems decompose rapidly at -78 C and could not be isolated or spectroscopicallycharacterized.